Hybrid vehicles are well known in the art. They are usually provided with an internal combustion engine (ICE), an electric traction motor that may transmit power to at least one wheel of the vehicle and an electric motor/generator used to supply electricity to the traction motor and/or to recharge batteries of the vehicle and/or to transmit power to at least one wheel of the vehicle.
A hybrid vehicle is said to be a series hybrid vehicle when the traction motor is used to drive the wheels and the ICE is exclusively used to drive the electric generator to recharge the vehicle's batteries and/or supply electric power directly to the traction motor.
A hybrid vehicle is said to be a parallel hybrid vehicle when both the traction motor and the ICE may be used simultaneously or individually to drive the wheels of the vehicle. In parallel hybrid vehicles, the ICE may also be used to recharge the batteries through the electric generator.
Series/parallel hybrid vehicles (SPHV) are also known in the art. Conventionally, these vehicles include drive trains that may be switched between a series mode and a parallel mode, as described hereinabove. SPHVs combine the series hybrid system with the parallel hybrid system in order to maximize the benefits of both systems. These vehicles generally have an electric motor and an electric generator, and depending on the driving conditions, use only the electric motor or the driving power from both the electric motor and the engine, in order to achieve the highest efficiency level. Furthermore, when necessary, the system drives the wheels while simultaneously generating electricity using a generator.